Emulsification apparatus



May 22, 1962 R. H. TODD ETAL 3,035,820

EMULSIFICATION APPARATUS Filed March 23, 1960 2 Sheets-Sheet 1 IN VENTOR.S

RICHARD H. TODD CURVIN D. STAMBAUGH ATTORNEY May 22, 1962 R. H. TODDETAL EMULSIFICATION APPARATUS 2 Sheets-Sheet 2 Filed March 25, 1960INVENTORS RICHARD H. TODD CURVIN D. STAMBAUGH ATTORNEY United StatesPatent 6 3,035,820 EMULSIFICATION APPARATUS Richard H. Todd and CurvinD. Stambaugh, Washington, D.C., assignors to Allergy Section of theResearch Foundation of Childrens Hospital of the District of Columbia,Washington, D.C., a corporation of the District of Columbia Fiied Mar.23, 1960, Ser. No. 17,862 4 Claims. (Cl. 259-98) The present inventionrelates to mechanically actuated pressure emulsification apparatus foremulsifying or homogenizing the suspension of solids or semi-solids in aliquid, such apparatus being of the type wherein the suspension ormixture is forced through a constricted passage at high velocity and/ orhigh pressures.

The apparatus of the present invention is particularly suitable formaking small quantities of emulsion and for being operated by manualpower, although its application is neither limited to small capacitiesnor to hand operation. A known form of pressure emulsor for producingemulsions such as those of oil and water consists of a pair of opposedsyringes or hypodermic members of the type including a syringe barrel orcylinder containing the mixture to be emulsified and having a plunger orpiston operable in each barrel or cylinder for repetitively transferringthe fluid from one syringe to the other through a constriction whichcouples the opposed cylinders to one another.

The high pressure secured in this apparatus forces the mixture orimperfect emulsion, which may, for example, be oil and Water, through anarrow passage at high pressure in order to perform the emulsification.As such mixture is transferred from one syringe to the other and theemulsification process proceeds, the viscosity of the resultant fluidincreases so as to require increasing pressure to be applied to thealternately actuated syringe plungers or pistons. It has been found thatsuch increasing pressures are ditficult to apply manually to the exposedend of the syringe piston, and in certain instances, the viscosity ofthe emulsion builds up to such a point that direct application ofincreased pressure as secured by a mechanical advantage is necessary.

Accordingly, it is a general oject of the present invention to providean apparatus for applying mechanical pressure to alternately actuate thesyringe pistons of an emulsification device of the type aforesaid.

A further object of the present invention is to provide apparatus foractuating an emulsor of the opposed syringe type so as to accommodatepaired syringes of different size or capacity.

Another oject of the present invention is to provide a device which isreadily and economically constructed and which permits a simple andefiicient use and operation thereof.

A still further object of the present invention is to provideemulsification apparatus of the type utilizing a pair of opposedhypodermic syringes wherein the syringes and the restricted transferpassage therebetween are protected against mechanical breakage due todistortion or misalignment during the application thereto of mechanicalforces which effect the emulsification process.

A more specific object of the present invention is to provide such anapparatus for applying mechanical forces to the aforesaid syringe typeemulsor, the parts of which are of simple construction, readily producedeconomically on a mass basis, and capable of adjustment after assemblyin order to accommodate syringe barrel structures and associatedcomponents of varying size, and permitting in a simple manner theintroduction and removal of the syringe apparatus.

The above and further objects, features, advantages,

ice

and applications of the present apparatus will be understood andappreciated by reference to the following de tailed description of apreferred embodiment of this invention, taken in conjunction with theaccompanying drawings, wherein:

FIG. 1 is a perspective view of the embodiment of the invention showingthe mechanical actuating apparatus operatively associated with thesyringe type emulsor;

FIG. 2 is a front elevational view of a portion of the emulsor apparatusto an enlarged scale;

FIG. 3 is a sectional View of the emulsor device illustrated in FIG. 2,taken substantially along the line 33 of FIG. 2; and

FIG. 4 is another sectional view of a second emulsor apparatus, takenalong a line such as that indicated as line 33 in FIG. 2; and representsa second application of the apparatus of the present invention.

Referring now specifically to the drawings, and in particular to FIG. 1thereof, there is shown a main base plate 1!) upon which the apparatusof the present invention is mounted. An elongated mechanical rack barmember 11 of generally rectangular cross section is slidably received ina groove 12 of corresponding dimensions which is provided in the baseplate 19'. Two or more bridging members 13 are provided in order tosecure the rack member in an operative relationship within the groove ortrack 12. The upper surface of bar 11 is provided with rack teeth 14,which may be formed directly therein as by a cutting or millingoperation, or may be afiixed thereto as a separate element which thenbecomes an integral part with the rack bar. Operatively associated withthe rack teeth 14 is the gear member 15 of basically circularconfiguration. Gear teeth 16 are provided in at least a portion of theouter periphery of member 15 and such teeth are of a size, spacing andconfiguration so as to mesh with teeth 14 of member 11. A central axle18 extends from either side of gear 15 and supports the same in a fixedelevational relation with respect to the rack bar for rotationalmovement with respect thereto by means of the journal blocks 17. Blocks17 are atfixed to the base plate 10 on either side of the groove 12 byany convenient method, for example, as by welding in the case ofmetallic elements, or by a suitable adhesive and/ or mechanical fixingmeans in the case of non-metallic elements.

A pair of actuating arms 19 extend outwardly from the rack bar 11 in aplane parallel to and spaced from that of the base member it atsubstantially right angles to the member 11. Arms 1? are fixed to themember 11 by any convenient means, such as that indicated by the screwmembers in FIG. 1, for unitary movement together with the rack bar in adirection parallel to the face of base member 16 and longitudinal of themajor axis of element 11.

A pair of adjustable clamping members 21 are fixed to the base plate 10in spaced parallel relationship by any convenient means such as thatindicated by the screw elements as shown in the drawings. The clampingmembers 21 may include opposed hinged jaws 22 which are movable towardone another by means of the threaded screw member 23 and wing nut 24 soas to securely clamp the syringe barrels 28 in fixed relationship withthe emulsification apparatus. At least the inner faces of jaws 22 arepreferably covered with a cushioning and facing means having arelatively high coefficient of friction as is indicated by the portion37 in the drawing so as to securely clamp the syringe barrel 20. Acoaxial spring 25 is mounted upon the screw 23 so that when the pressureof the jaws is released by rotation of the wing nut 24 the jaws may openso as to permit removal of the emulsor apparatus.

The emulsor apparatus consists of a pair of hypodermic syringes, each ofwhich are indicated by the reference numeral 20, as applied to thebarrel portion thereof, and they further include a piston member 29which may be reciprocated within the barrel in order force the fiuidcontents thereof through a constricted communicating pas sage 36 betweenthe paired syringe barrels. Pressure is applied alternately to the headof one and then to the other of the opposed syringe pistons by means ofarms 19 which are reciprocated by the rack bar 11. Pressure istransmitted from each arm 19 to the head of the piston 29 by means ofthe adjustable screw element 26, the position of which may be regulatedby means of the knurled head e ement at 27, and is directly applied tothe head of the piston by means of the bearing member 28 which isattached to the end of screw member 26. Cushioning facing means may beprovided on member 23. During the operation of the emulsificationapparatus of this invention, as described in detail hereinafter, thegear is rotated on its axle 33 by alternate reciprocation of theoperating handle 39 so as to reciprocate the rack element and theattached arms 19. During the repetitive passage of the fiuid through therestriction 36 the pressures are such as to cause an increase inviscosity of the mixture as it approaches the final emulsifiedcondition.

The combination of the paired opposed syringes 2% is thus subjected toincreased pressures and the reciprocation of the pistons 29 of thesyringes becomes increasingly difficult, due to the large pressuretransmission and reaction forces which build up. The magnitude of theseforces are such as to cause the possibility of undesired movements ofthe paired syringes either in a direction longitudinal of their commonaxis or transverse thereto, or both. Either direction of movement shouldbe avoided as it results in a loss of efiiciency, but of the two thetransverse movement is to be particularly avoided. The transversemovement may be such as to cause the common connection between thesyringes to buckle or deflect away from its normal axial position withpossible distortion or fracture of the constricted passage 36, or thecouplings which attach the same to syringes 2%, or of the syringe barrelat such coupling point. According to an important feature of the presentinvention, one or more pillow block clamping fixtures or centeringassemblies designated generally by the reference character 33 areprovided in order to obviate the above mentioned possibilities.

As indicated in FIGS. 2 through 4 of the drawings the constriction whichconnects the paired syringes of the emulsor system is of minimumdiameter and thus such interconnection is subjected to the maximumforces developed in the system. The constriction 36 in its simplest formmay consist merely of a portion of a conventional hypodermic'needlewhich is secured between two standard couplings, which couplings arereleasably attached to the base of each syringe barrel. The centeringassembly 36 is shown in particular detail in FIGURES 3 and 4. Referringnow to FIG. 3, a portion of base plate it) is shown in the area adjacentto the mounting of such clamping fixture. Assembly 34. consists of apair of spaced posts 31 which are fixed into the base member 16 as bythreading therein on either side of the axis of the emulsor; morespecifically the axis of the constricted portion 36 thereof. Twocomplementary blocks 32 and 33 are provided to. engage the outer surfaceof the restriction element 36, and such blocks are counterbored in orderto be releasably secured upon the posts 31. A spacer block 35 may beutilized in combination with blocks 32 and 33 as indicated in FIG. 3 inorder to bring the semi-circular jaw openings 49 and 41 into axialalignment with the longitudinal axis of the hypodermic barrel 2% and tie constriction member 36. Clamp nuts 34 are threadedly received upon theposts 31 in order to rigidly hold member 36 between the blocks 32, 33and thereby maintain the same in fixed relationship to the base memberSid. Cushioned lining means 42 and 43 are advantageously incorporated injaws as and 41 to assist inthe clamping action.

It will be apparent to those skilled in the art that hypodermic syringesare available in various volumetric sizes and that, as such, thediameter of the cylinders thereof vary accordingly. it is one of theadvantages of the present invention that paired hypodermic syringeemulsors of varying capacities and therefore of varying sizes may beaccommodated by the apparatus. For example, the syringe 2i? as shown inFIGS. 1 through 3 may be of a capacity of 20 cc. In the event thatemulsor syringes of a smaller quantity are to be utilized with theapparatus, for example, of a 10 cc. capacity, as indicated at 2% in FIG.4, then it will be apparent that the transverse diameter and radius ofsuch smaller syringes will be less than that shown for the 20 cc.syringe of the embodiment depicted in FIG. 3. When paired syringes ofsuch lesser quantity are utilized with the present invention, the spacerblocs's 35 shown in FIG. 3 is removed from posts 31 and the assembly 38appears as shown in FIG. 4. By means of a series of spacer blocks 35 itis possible, according to he concept of the invention, to accommodatepaired syringe emulsors of variable capacity, and particularly toutilize the apparatus to prepare very small quantities of emulsion.

The operation of the emulsification apparatus of the present inventionwill now be apparent. The paired syringe emulsor is first prepared byplacing the piston of one syringe at the end of the barrel adjacent tothe constriction 3'6 and removing the piston of the opposite syringe.The mixture which is to be emulsified is then introduced into the opensyringe barrel and its piston 29 is then replaced. The emulsor assemblyis then placed within the emulsification apparatus by opening eachclamping member 21 and also removing the nuts 34 and upper clampingblock 32 from the assembly 30. Rack bar 11 is next moved by means of thehandle 39 so as to place the arms 19 in such a position as toaccommodate the piston faces of the emulsor apparatus. The emulsorapparatus is then introduced within the clamps 21 which are securelyfastened down to the syringe barrels 20, and the block 32 of theclamping fixture 30 is replaced and nuts 34 are tightened to hold theconstriction member 36 in fixed relationship to the base plate 10. Screwelements 26 are then adjusted so as to place the bearing members 28against the outer operating faces of the two pistons 29. The operatorthen manipulates the handle 39 back and forth to reciprocate rack bar 11and thus to alternately apply an actuating force to the pistons 29 so asto force the mixture Within the syringe barrels through the constrictedpassage 36 at high velocities and pressures to properly emulsify theliquid mixture.

When the emulsification has progressed to a statisfactory state, whichwill be apparent to the operator based upon one or more of the followingfactors, such as the experience of the operator, the number of transfersof the solution from one syringe to the other, the physical appearanceof the emulsion when transparent syringe barrels are utilized, or theobservable increase in pressure necessary to be applied at the handle39, the movement of such handle is stopped. Clamp nuts 24 and 34 arethen released, as are the screw elements 26, and the emulsor assembly isremoved from the apparatus. At this time the emulsion product willpreferably all rest within one syringe, and the constricted coupling 36between the paired syringes may be released, thus permitting theoperator to readily handle the resulting emulsion which is now containedwithin one hypodermic syringe. It will be apparent that such anemulsion-filled syirnge may now be conveniently handled for subsequentuse thereof. For example, a sterile closure may be applied to the baseof the syringe barrel in order that the emulsion may be stored for lateruse, or a hypodermic needle may be attached to the syringe barrel in theevent that immediate infusion of the emulsification product is to beeffected. With the emulsification of the mixture completed, the emptyhypodermic syringe and constriction assembly 36' may be stressed readilycleansed and sterilized in the usual manner with conventional equipment.The emulsification apparatus by which the mechanical application ofpressures to the emulsor is efiected need not be cleaned or sterilizedsince no part thereof has come into contact with the liquid which hasbeen emulsified.

Numerous modifications may be made to the preferred embodiment of theapparatus as described above, for example the reciprocation of the rackbar 11 may be effected by means other than the gear 15 and manualoperating handle 39. The end face 11A of the bar 11 may be utilized as acam follower and be alternately driven or displaced in a reciprocalmanner by means of a rotary motor and cam arrangement of any known type.If such motor-driven cam actuation is not of the type which produces apower stroke for each reciprocal direction, then it would be obvious tomodify the apparatus further by the provision of a return biasing springwhich would be attached to the opposite end face 11B of the rack bar andto the base plate 10. Further possible modifications of theemulsification apparatus will also be apparent, for example, theclamping members 21 could be replaced by a substitute equivalentstructure of the type shown in the pillow block clamping fixture orcentering assembly 30.

It should further be noted that while the preferred embodiment of theemulsification apparatus of this invention has been described assuitable for particular application with an emulsor of the opposedhypodermic syringe type, such apparatus is also capable of applicationand utilization with similar opposed piston assemblies to whichmechanical reciprocal forces are to be applied. For example, theapparatus of the present invention could be utilized with the opposedsyringe viscosity testing assembly shown in the US. patent to Hain No.2,447,598.

Further, while the opposed syringe assembly to which mechanicalreciprocal forces are applied by the apparatus of the present inventionhas been designated as an emulsor for emulsifying or homogenizing asuspension of solids or semi-solids in a liquid, the term emulsor mayalso equally apply to assemblies utilized for emulsifying orhomogenizing a mixture or suspension of solids or semisolids in a solidor semi-solid vehicle as in the preparation of ointments. A recognizeddefinition of an ointment being a vehicle such as lard, lard and wax, orpetrolatum in which some addition substance has been incorporated andthoroughly intermixed and dispersed.

It is therefore intended that all matter contained in the abovedescription or shown in the accompanying drawings shall be interpretedas illustrative only and not in a limiting sense.

What is claimed is:

1. A mechanically actuated emulsification apparatus including, incombination, a hydraulic pressure emulsification device comprising apair of spaced opposed cylindrical syringe barrels interconnectedmechanically and hydraulically by a coaxial emulsor member, each barrelhaving a piston mounted therein for reciprocal movement of a givenstroke length, a base plate, means to clamp said emulsification deviceto said base plate with the pistons extending outwardly at opposite endsof the device disposed along an axial line of action spaced from andparallel to said base plate, a force transmitting member mounted on saidbase plate for reciprocal motion parallel to said axial line of action,a pair of spaced arms extending outwardly from said force transmittingmember, the free end of each arm bearing upon one of said pistons andthe spacing between such arms being such that when a first piston isreciprocated a complete stroke length inwardly toward theinterconnecting emulsor member the second piston may be reciprocated acomplete stroke length outwardly away from such member, and means toapply areciprocating force to said force transmitting member toalternately drive said first piston and said second piston inwardly.

2. Apparatus according to claim 1 wherein said means to clamp saidemulsification device includes first clamping means to secure eachsyringe barrel in fixed relation above said base plate, and secondclamping means to secure said interconnecting coaxial emulsor member infixed relation above'said base plate and spaced therefrom a distancedetermined by the diameter of the cylindrical syringe barrels.

3. Apparatus as set forth in claim 2 wherein said second clamping meansincluding a plurality of spacer elements for selective use as determinedby the diameter of the cylindrical syringe barrels.

4. Apparatus as set forth in claim 3 wherein each such spacer elementhas a different relative distance dimension which is directlyproportional to the diameter of the cylindrical syringe barrel.

References Cited in the file of this patent UNITED STATES PATENTS1,288,966 Nielsen Dec. 24, 1918 2,071,879 Jolma Feb. 23, 1937 2,477,598Hain Aug. 2, 1949 2,948,920 Hausmann Aug. 16, 1960 FOREIGN PATENTS683,567 Germany Nov. 9, 1939 414,957 Great Britain Aug. 16, 1934 UNITEDSTATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 0351320 May22, 1962 Richard H. Todd et a1.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 1 lines 44 and 52, for "oject", each occurrence,

read object column 4, line 17, for "blocks" read lolock column 6, line34, for "including" read lnclude Signed and sealed this 16th day ofOctober 1962.

(SEAL) Attest:

ERNEST w. SWIDER DAVID LADD Attesting Officer Commissioner of Patents

